A hydrophilic modified polypropylene non-woven fabric, its preparation method and application

Abstract

The present invention provides a hydrophilic modified polypropylene non-woven fabric. For the hydrophilic modified polypropylene non-woven fabric provided by the present invention, the grafting rate of the functional monomer is relatively high. Together with the self-polymerization component of the functional monomer, the obtained hydrophilic modified polypropylene non-woven fabric has stronger hydrophilicity. Moreover, after adding a non-reactive inorganic or organic auxiliary agent to the solvent, the mixing becomes more uniform, the product batches are more stable, and there are no special requirements for the equipment. Therefore, compared with the traditional surface treatment method, the hydrophilic effect of the present invention is more lasting.

Description

Technical Field

[0001] The present invention belongs to the technical field of non-woven fabrics, and particularly relates to a hydrophilic modified polypropylene non-woven fabric, a preparation method thereof, and an application thereof. Background Art

[0002] Polypropylene non-woven fabrics have excellent filtration performance, and their raw materials are rich in sources, the processing process is simple, and the cost is low. They have been widely used in the fields of water treatment and air filtration. In the field of water treatment, since polypropylene is a hydrophobic polymer, in order to increase the water treatment flux, it must be hydrophilically modified. Common hydrophilic modification methods include physical blending, grafting blending, surface coating, surface chemical treatment, plasma treatment, and ozone treatment. Although the above methods have significantly improved the problem of poor hydrophilicity of polypropylene non-woven fabrics, these methods all have certain defects: physical blending is difficult to ensure the uniformity and compatibility between multi-components; the coating formed by the surface coating method has poor durability and is easy to fall off; surface chemical treatment takes a long time and is easy to produce pollution; the treatment of non-woven fabrics by the grafting method and the radiation grafting method requires a long treatment time; the plasma method is not easy to control and will cause die hole blockage; the surface ozone treatment method has high treatment costs and serious environmental pollution. Grafting blending is a common method for the preparation of modified polypropylene non-woven fabrics, but the grafting blending process has a strong smell, which is particularly unfriendly to volatile graft monomers, resulting in a low grafting rate and affecting the hydrophilic performance. Summary of the Invention

[0003] In view of this, the technical problem to be solved by the present invention is to provide a hydrophilic modified polypropylene non-woven fabric, a preparation method thereof, and an application thereof. The polypropylene non-woven fabric provided by the present invention has a higher grafting rate, and with the addition of the self-polymer component of the monomer, the non-woven fabric has stronger hydrophilicity.

[0004] The present invention provides a hydrophilic modified polypropylene non-woven fabric, comprising:

[0005] 49wt% - 99wt% of modified polypropylene, which is a product with a grafting rate of 3% - 60% obtained by solution grafting modification of polypropylene with a functional monomer;

[0006] 1wt% - 20wt% of self-polymer of the functional monomer;

[0007] 0wt% - 50wt% of additives;

[0008] The sum of the above components is 100%;

[0009] The functional monomer is selected from one or a combination of at least two of hydroxyethyl methacrylate, methacrylamide, maleic anhydride, maleic acid, acrylic acid, styrene, 2-(2-hydroxy-3-tert-butyl-5-methylbenzyl)-4-methyl-6-tert-butylphenyl acrylate, N-(4-anilinophenyl)methacrylamide, N-(4-anilinophenyl)maleimide, N-(3-methacryloyloxy-2-hydroxymethyl)-N'-phenyl-p-phenylenediamine, 2,4,6-triallylphenol, 3,5-di-tert-butyl-4-hydroxybenzyl acrylate, etc.

[0010] Preferably, the auxiliary agent is selected from one or more of antioxidants, antibacterial agents, and flame retardants.

[0011] Preferably, the antioxidant includes one or a combination of at least two of pentaerythritol tetra[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], dibutylhydroxytoluene, tert-butylhydroquinone, octadecyl β(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene;

[0012] The antibacterial agent includes one or a combination of at least two of ZIF-8, Ag, Ag@ZIF-8, polyhexamethylene guanidine, graphene;

[0013] The flame retardant includes one or a combination of at least two of tris(nonylphenyl) phosphite, dipentaerythritol diphosphite, ammonium polyphosphate, pentaerythritol, triazine charring agent, magnesium hydroxide, aluminum hydroxide, antimony oxide, etc.

[0014] Preferably, the non-woven fabric is a spunbond non-woven fabric or a meltblown non-woven fabric.

[0015] The present invention also provides a method for preparing the above hydrophilic modified polypropylene non-woven fabric, which includes the following steps:

[0016] A) Mix polypropylene, a functional monomer, an auxiliary agent, and an organic solvent, and carry out a heating reaction to obtain a reaction product;

[0017] After removing the solvent from the reaction product, granulate to obtain modified polypropylene;

[0018] B) Prepare the modified polypropylene into a non-woven fabric to obtain a hydrophilic modified polypropylene non-woven fabric.

[0019] Preferably, the mass ratio of polypropylene to the functional monomer is 100:150 to 100:5.

[0020] The functional monomers include the functional monomers participating in the grafting reaction and the functional monomers not participating in the grafting reaction, and the mass ratio of the functional monomers participating in the grafting reaction to the functional monomers not participating in the grafting reaction is 9.99:0.01 to 1:9.

[0021] Preferably, the organic solvent is selected from one or a combination of at least two of straight-chain alkanes, isoparaffins, cycloalkanes or aralkyl hydrocarbons having 4 to 10 carbon atoms.

[0022] Preferably, the temperature of the heating reaction is 60 to 190 °C, and the time is 10 to 600 min.

[0023] Preferably, the method for preparing the modified polypropylene into a non-woven fabric includes a spunbond process or a meltblown process.

[0024] The present invention also provides an application of the above hydrophilic modified polypropylene non-woven fabric as a filter medium.

[0025] Compared with the prior art, the present invention provides a hydrophilic modified polypropylene non-woven fabric, including: 49 wt% to 99 wt% of modified polypropylene, which is a product with a grafting rate of 3% to 60% obtained by solution grafting modification of polypropylene with functional monomers; 1 wt% to 20 wt% of self-polymers of functional monomers; 0 wt% to 50 wt% of additives; the functional monomers are selected from one or a combination of at least two of hydroxyethyl methacrylate, methacrylamide, maleic anhydride, maleic acid, acrylic acid, styrene, 2-(2-hydroxy-3-tert-butyl-5-methylbenzyl)-4-methyl-6-tert-butylphenyl acrylate, N-(4-anilinophenyl)methacrylamide, N-(4-anilinophenyl)maleimide, N-(3-methacryloyloxy-2-hydroxymethyl)-N'-phenyl-p-phenylenediamine, 2,4,6-triallylphenol or 3,5-di-tert-butyl-4-hydroxybenzyl acrylate, etc. The hydrophilic modified polypropylene non-woven fabric provided by the present invention has a relatively high grafting rate of functional monomers. Coupled with the self-polymerized component of the functional monomers, the obtained hydrophilic modified polypropylene non-woven fabric has stronger hydrophilicity. Moreover, after adding non-reactive inorganic or organic additives to the solvent, the mixing is more uniform, the product batches are more stable, and there are no special requirements for equipment. Therefore, compared with the traditional surface treatment method, the hydrophilic effect of the present invention is more lasting. Detailed Embodiments

[0026] The present invention provides a hydrophilic modified polypropylene non-woven fabric, including:

[0027] 49 wt% to 99 wt% of modified polypropylene, which is a product with a grafting rate of 3% to 60% obtained by solution grafting modification of polypropylene with functional monomers;

[0028] Homopolymers of 1 wt% to 20 wt% of functional monomers;

[0029] 0 wt% to 50 wt% of additives;

[0030] The functional monomers are selected from one or a combination of at least two of hydroxyethyl methacrylate, methacrylamide, maleic anhydride, maleic acid, acrylic acid, styrene, 2-(2-hydroxy-3-tert-butyl-5-methylbenzyl)-4-methyl-6-tert-butylphenyl acrylate, N-(4-anilinophenyl)methacrylamide, N-(4-anilinophenyl)maleimide, N-(3-methacryloyloxy-2-hydroxymethyl)-N'-phenyl-p-phenylenediamine, 2,4,6-triallylphenol, 3,5-di-tert-butyl-4-hydroxybenzyl acrylate, etc.

[0031] The hydrophilic modified polypropylene non-woven fabric provided by the present invention comprises 49 wt% to 99 wt% of modified polypropylene, preferably 49 wt%, 50 wt%, 52 wt%, 55 wt%, 58 wt%, 60 wt%, 65 wt%, 70 wt%, 75 wt%, 80 wt%, 85 wt%, 90 wt%, 95 wt%, 99 wt%, or any value between 49 wt% and 99 wt%, further preferably any value between 69 wt% and 98%, and more preferably any value between 79 wt% and 98%. In the present invention, the modified polypropylene is a product with a grafting rate of 3% to 60% obtained by solution grafting modification of polypropylene with functional monomers, wherein the grafting rate is preferably 3%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, or any value between 3% and 60%, further preferably any value between 5% and 20%, and more preferably any value between 10% and 20%.

[0032] The functional monomers are selected from one or a combination of at least two of hydroxyethyl methacrylate, methacrylamide, maleic anhydride, maleic acid, acrylic acid, styrene, 2-(2-hydroxy-3-tert-butyl-5-methylbenzyl)-4-methyl-6-tert-butylphenyl acrylate, N-(4-anilinophenyl)methacrylamide, N-(4-anilinophenyl)maleimide, N-(3-methacryloyloxy-2-hydroxymethyl)-N'-phenyl-p-phenylenediamine, 2,4,6-triallylphenol, 3,5-di-tert-butyl-4-hydroxybenzyl acrylate, etc., and preferably hydroxyethyl methacrylate.

[0033] The hydrophilic modified polypropylene non-woven fabric provided by the present invention further comprises a homopolymer of a functional monomer in an amount of 1 wt% to 20 wt%, preferably 1 wt%, 3 wt%, 5 wt%, 8 wt%, 10 wt%, 12 wt%, 15 wt%, 17 wt%, 20 wt%, or any value between 1 wt% and 20 wt%, more preferably any value between 5 wt% and 20 wt%, and still more preferably any value between 10 wt% and 20 wt%.

[0034] The homopolymer of the functional monomer is one or a combination of at least two of poly (2-hydroxyethyl methacrylate), polyacrylamide, poly (maleic anhydride), poly (maleic acid), polyacrylic acid, polystyrene, poly [2-(2-hydroxy-3-tert-butyl-5-methylbenzyl)-4-methyl-6-tert-butylphenyl acrylate], poly [N-(4-aminophenyl)phenyl methacrylamide], poly [N-(4-aminophenyl)maleimide], poly [N-(3-methacryloyloxy-2-hydroxymethyl)-N'-phenyl-p-phenylenediamine], poly (2,4,6-triallylphenol), or 3,5-di-tert-butyl-4-hydroxybenzyl acrylate, etc., or a copolymer of at least two of the functional monomers.

[0035] The hydrophilic modified polypropylene non-woven fabric provided by the present invention further comprises an auxiliary agent in an amount of 0 wt% to 50 wt%, preferably 0%, 5%, 10%, 20%, 30%, 40%, 50%, or any value between 0 wt% and 50 wt%, more preferably any value between 1 wt% and 25 wt%, and still more preferably any value between 1 wt% and 10 wt%.

[0036] In the present invention, the auxiliary agent is selected from one or more of antioxidants, antibacterial agents, and flame retardants.

[0037] The antioxidants include one or a combination of at least two of pentaerythritol tetra [β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], dibutylhydroxytoluene, tert-butylhydroquinone, octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene;

[0038] The antibacterial agents include one or a combination of at least two of ZIF-8, Ag, Ag@ZIF-8, polyhexamethylene guanidine, graphene;

[0039] The flame retardants include one or a combination of at least two of tris(nonylphenyl) phosphite, dipentaerythritol diphosphite, ammonium polyphosphate, pentaerythritol, triazine charring agent, magnesium hydroxide, aluminum hydroxide, antimony oxide, etc.

[0040] The raw material of the non-woven fabric provided by the present invention is obtained by solution method modification, and the obtained product has a controllable grafting rate and uniform components; moreover, when using volatile functional monomers for modification, the operation is friendly and the grafting rate is high; in addition, a multi-component copolymerization grafting product can be obtained.

[0041] In the present invention, the non-woven fabric is preferably a spunbond non-woven fabric or a meltblown non-woven fabric.

[0042] The present invention also provides a preparation method of the above hydrophilic modified polypropylene non-woven fabric, comprising the following steps:

[0043] A) Mix polypropylene, a functional monomer, an auxiliary agent and an organic solvent, and carry out a heating reaction to obtain a reaction product;

[0044] After removing the solvent from the reaction product, granulate to obtain modified polypropylene;

[0045] B) Prepare the modified polypropylene into a non-woven fabric to obtain a hydrophilic modified polypropylene non-woven fabric.

[0046] The present invention first mixes polypropylene, a functional monomer, an auxiliary agent and an organic solvent, and carries out a heating reaction to obtain a reaction product;

[0047] Among them, the present invention has no special limitation on the source of the polypropylene, and the polypropylene known to those skilled in the art and available for preparing polypropylene non-woven fabrics can be used, which can be a commercially available product or can be prepared by oneself.

[0048] The ratio of the polypropylene to the functional monomer is 100:150 to 100:5, preferably 100:150, 100:140, 100:130, 100:120, 100:100, 100:80, 100:60, 100:50, 100:40, 100:20, 100:10, 100:5, or any value between 100:150 and 100:5.

[0049] The functional monomer includes the functional monomer participating in the grafting reaction and the functional monomer not participating in the grafting reaction, and the mass ratio of the functional monomer participating in the grafting reaction to the functional monomer not participating in the grafting reaction is 9.99:0.01 to 1:9, preferably 9.99:0.01, 9:1, 8:2, 7:3, 6:4, 5:5, 4:6, 3:7, 2:8, 1:9, or any value between 9.99:0.01 and 1:9.

[0050] The organic solvent is selected from one or a combination of at least two of straight-chain alkanes, isoparaffins, naphthenes or aralkyls having 4 to 10 carbon atoms, and is preferably toluene.

[0051] The temperature of the heating reaction is 60 to 190 °C, preferably 60, 80, 100, 120, 140, 160, 180, 190, or any value between 60 and 190 °C, and the time is 10 to 600 min, preferably 10, 30, 60, 90, 120, 240, 360, 480, 600, or any value between 10 and 600 min.

[0052] After obtaining the reaction product, the solvent of the reaction product is removed and then granulated to obtain modified polypropylene.

[0053] The present invention has no special limitation on the method for removing the solvent, and any method known to those skilled in the art can be used. In the present invention, it is preferred to use the methods of flash evaporation and deashing to remove the solvent.

[0054] After obtaining the modified polypropylene, the modified polypropylene is made into a non-woven fabric to obtain a hydrophilic modified polypropylene non-woven fabric.

[0055] The present invention has no special limitation on the method for preparing the non-woven fabric, and any method for preparing non-woven fabrics known to those skilled in the art can be used.

[0056] In the present invention, it is preferred to use the spunbond process or the meltblown process to prepare the non-woven fabric.

[0057] The present invention also provides an application of the above hydrophilic modified polypropylene non-woven fabric as a filter medium.

[0058] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0059] (1) Due to the use of the solution modification process, compared with the traditional screw extrusion graft copolymerization modification, the grafting rate of the polypropylene non-woven fabric is higher. Coupled with the self-polymerization component of the monomer, the non-woven fabric has stronger hydrophilicity.

[0060] (2) Compared with the traditional physical blending modification by screw extrusion, adding non-reactive inorganic or organic substances in the solvent makes the mixing more uniform, the product batches more stable, and there are no special requirements for the equipment.

[0061] (3) Compared with the traditional surface treatment method, the hydrophilic effect of the present invention is more persistent.

[0062] To further understand the present invention, the following examples are used to illustrate the hydrophilic modified polypropylene non-woven fabric provided by the present invention, its preparation method and application. The protection scope of the present invention is not limited by the following examples.

[0063] Example 1

[0064] 1) Mix 20 parts of polypropylene, 5 parts of 2-hydroxyethyl methacrylate, 80 parts of toluene, and 0.2 parts of benzoyl peroxide by weight, react at 120 °C for 3 hours, and after flash evaporation and deashing to remove toluene, granulate to obtain modified polypropylene.

[0065] 2) After melting the polypropylene in 1) by screw extrusion, extrude it from the spinneret assembly to form filaments, and form a fiber web on the forming screen after air cooling. After reinforcement, a new type of polypropylene spunbond non-woven fabric is obtained. The composition of this non-woven fabric is obtained by ethanol separation and titration method respectively: 85.1% of the modified product, 14.9% of poly(2-hydroxyethyl methacrylate), and the grafting rate of the modified product is 11.1%.

[0066] 3) Measure the hydrophilicity of this non-woven fabric with a contact angle measuring instrument, and the measured contact angle is 54°.

[0067] 4) Under a transmembrane pressure difference of 1 kPa, rinse the non-woven fabric with deionized water for 2 h, and measure the pure water flux, which is 35010 L / m 2 / h. After the 5th flushing, the pure water flux is 35002 L / m 2 / h, basically remaining unchanged, indicating that this non-woven fabric has very good durability.

[0068] Example 2

[0069] 1) Mix 20 parts of polypropylene, 5 parts of 2-hydroxyethyl methacrylate, 80 parts of toluene, 0.2 parts of benzoyl peroxide, and 0.1 part of silver nanoparticles by weight, react at 120 °C for 3 hours, and after flash evaporation and deashing to remove toluene, granulate to obtain modified polypropylene.

[0070] 2) After melting the polypropylene in 1) by screw extrusion, use a high-temperature air flow of 260 °C to blow and stretch the melt to form ultrafine fibers, and collect them on the forming screen to obtain a new type of polypropylene meltblown non-woven fabric. The composition of this non-woven fabric is obtained by ethanol separation and titration method respectively: 90.4% of the modified product, 9.6% of poly(2-hydroxyethyl methacrylate), and the grafting rate of the modified product is 11.5%.

[0071] 3) Measure the hydrophilicity of this non-woven fabric with a contact angle measuring instrument, and the measured contact angle is 61°.

[0072] 4) Use the test method in GB / T 20944.3 to detect the antibacterial effect of the antibacterial meltblown non-woven fabric on Escherichia coli. The bactericidal rate is greater than 99% after 9 hours, and the bactericidal rate reaches 100% after 18 hours.

[0073] 5) Under a transmembrane pressure difference of 1 kPa, rinse the non-woven fabric with deionized water for 2 h, and measure the pure water flux, which is 34289 L / m 2 / h. After the 5th flushing, the pure water flux is 34150 L / m 2 / h, basically remains unchanged, indicating that the non-woven fabric has very good durability.

[0074] Example 3

[0075] 1) By weight, 20 parts of polypropylene, 5 parts of acrylic acid, 80 parts of toluene, and 0.2 part of benzoyl peroxide were mixed and reacted at 90 °C for 3 hours. After flash evaporation and ash removal to remove toluene, granulation was carried out to obtain modified polypropylene.

[0076] 2) The polypropylene in 1) was extruded and melted by a screw and then ejected from the spinneret assembly to form filaments. After air cooling, a fiber web was formed on the forming screen, and after reinforcement, a new type of polypropylene spunbond non-woven fabric was obtained. By using ethanol separation and titration method respectively, the composition of this non-woven fabric was obtained as follows: 87.2% of the modified product, 12.8% of polyacrylic acid, and the grafting rate of the modified product was 8.4%.

[0077] 3) The hydrophilicity of this non-woven fabric was measured using a contact angle measuring instrument, and the measured contact angle was 51°.

[0078] Example 4

[0079] 1) By weight, 20 parts of polypropylene, 5 parts of methacrylamide, 80 parts of toluene, and 0.2 part of benzoyl peroxide were mixed and reacted at 100 °C for 6 hours. After flash evaporation and ash removal to remove toluene, granulation was carried out to obtain modified polypropylene.

[0080] 2) The polypropylene in 1) was extruded and melted by a screw and then ejected from the spinneret assembly to form filaments. After air cooling, a fiber web was formed on the forming screen, and after reinforcement, a new type of polypropylene spunbond non-woven fabric was obtained. By using ethanol separation and titration method respectively, the composition of this non-woven fabric was obtained as follows: 98.1% of the modified product, 1.9% of polymethacrylamide, and the grafting rate of the modified product was 18.6%.

[0081] 3) The hydrophilicity of this non-woven fabric was measured using a contact angle measuring instrument, and the measured contact angle was 48°.

[0082] Example 5

[0083] 1) By weight, 20 parts of polypropylene, 3 parts of styrene, 3 parts of maleic anhydride, 80 parts of toluene, and 0.2 part of benzoyl peroxide were mixed and reacted at 100 °C for 6 hours. After flash evaporation and ash removal to remove toluene, granulation was carried out to obtain modified polypropylene.

[0084] 2) The polypropylene in 1) was extruded and melted by a screw and then ejected from the spinneret assembly to form filaments. After air cooling, a fiber web was formed on the forming screen, and after reinforcement, a new type of polypropylene spunbond non-woven fabric was obtained. By using ethanol separation and titration method respectively, the composition of this non-woven fabric was obtained as follows: 98.9% of the modified product, 1.1% of styrene, maleic anhydride homopolymer and copolymer, and the grafting rate of the modified product was 22.2%.

[0085] 3) The hydrophilicity of the non-woven fabric was measured using a contact angle measuring instrument, and the contact angle was measured to be 65°. Comparative example

[0086] One of the features of the present invention is that it is possible to use a high content of volatile graft monomers that are not friendly to the traditional screw extrusion grafting and blending modification method. For comparison:

[0087] 1) By weight, 100 parts of polypropylene, 2 parts of maleic anhydride, 0.2 parts of DCP, and 0.2 parts of [2,4-di-tert-butylphenyl] phosphite were mixed evenly in a high-speed mixer and added to a twin-screw extruder, and granulated to obtain modified polypropylene. The length-diameter ratio of the twin-screw was 55:1, the temperature in zones 1-5 was 160-180 °C, the temperature in zones 6-10 was 190-230 °C, the temperature in zone 11 and above was 190-200 °C, and the rotation speed was set at 200 r / min. During the experiment, there was an obvious pungent smell.

[0088] 2) After the polypropylene in 1) was extruded and melted by a screw, the melt was stretched by high-temperature air blowing to form ultrafine fibers, which were collected on a forming screen to obtain a new type of polypropylene meltblown non-woven fabric. The grafting rate of the non-woven fabric was obtained by ethanol separation and titration method to be 0.9%.

[0089] 3) The hydrophilicity of the non-woven fabric was measured using a contact angle measuring instrument, and the contact angle was measured to be 97°, showing hydrophobicity, and the hydrophilic modification effect was inferior to that of the example.

[0090] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A hydrophilic modified polypropylene non-woven fabric, characterized in that, The raw materials are as follows: 49wt% - 99wt% of modified polypropylene, which is a product with a grafting rate of 3% - 60% obtained by solution grafting modification of polypropylene with a functional monomer; 1wt% - 20wt% of the homopolymer of the functional monomer; 0wt% - 50wt% of additives; The sum of the above components is 100%; The functional monomer is selected from one or a combination of at least two of 2 - hydroxyethyl methacrylate, methacrylamide, maleic anhydride, maleic acid, acrylic acid, styrene, 2-(2 - hydroxy - 3 - tert - butyl - 5 - methylbenzyl)-4 - methyl - 6 - tert - butylphenyl acrylate, N-(4 - anilinophenyl)methacrylamide, N-(4 - anilinophenyl)maleimide, N-(3 - methacryloyloxy - 2 - hydroxymethyl)-N'-phenyl - p - phenylenediamine, 2,4,6 - triallylphenol or 3,5 - di - tert - butyl - 4 - hydroxybenzyl acrylate.

2. The hydrophilic modified polypropylene non-woven fabric according to claim 1, characterized in that, The additives are selected from one or more of antioxidants, antibacterial agents, and flame retardants.

3. The hydrophilic modified polypropylene non-woven fabric according to claim 2, characterized in that, The antioxidant includes one or a combination of at least two of pentaerythritol tetra[β-(3,5 - di - tert - butyl - 4 - hydroxyphenyl)propionate], 2,6 - di - tert - butyl - 4 - methylphenol, tert - butylhydroquinone, octadecyl 3-(3,5 - di - tert - butyl - 4 - hydroxyphenyl)propionate, 1,3,5 - trimethyl - 2,4,6 - tris(3,5 - di - tert - butyl - 4 - hydroxybenzyl)benzene; The antibacterial agent includes one or a combination of at least two of ZIF - 8, Ag, Ag@ZIF - 8, polyhexamethylene guanidine, graphene; The flame retardant includes one or a combination of at least two of tris(nonylphenyl)phosphite, pentaerythritol diphosphite distearate, ammonium polyphosphate, pentaerythritol, triazine char - forming agent, magnesium hydroxide, aluminum hydroxide, antimony oxide.

4. The hydrophilic modified polypropylene non-woven fabric according to claim 1, characterized in that, The non - woven fabric is a spunbond non - woven fabric or a melt - blown non - woven fabric.

5. A preparation method of the hydrophilic modified polypropylene non-woven fabric according to any one of claims 1 to 4, characterized in that, It includes the following steps: A) Mix polypropylene, functional monomer, additives and organic solvent, and carry out a heating reaction to obtain a reaction product; After removing the solvent from the reaction product, granulate to obtain modified polypropylene; B) Prepare the modified polypropylene into a non - woven fabric to obtain a hydrophilic modified polypropylene non - woven fabric.

6. The preparation method according to claim 5, characterized in that, The mass ratio of polypropylene to the functional monomer is 100:150 - 100:5; The functional monomer includes the functional monomer participating in the grafting reaction and the functional monomer not participating in the grafting reaction, and the mass ratio of the functional monomer participating in the grafting reaction to the functional monomer not participating in the grafting reaction is 9.99:0.01 - 1:

9.

7. The preparation method according to claim 5, characterized in that, The organic solvent is selected from one or a combination of at least two of straight - chain alkanes, isoparaffins, naphthenes or alkyl aromatics having 4 - 10 carbon atoms.

8. The preparation method according to claim 5, characterized in that, The temperature of the heating reaction is 60 - 190 and the time is 10 - 600 min.

9. The preparation method according to claim 5, characterized in that, The method of preparing the modified polypropylene into a non - woven fabric includes a spunbond process or a melt - blown process.

10. An application of the hydrophilic modified polypropylene non-woven fabric according to any one of claims 1 to 4 as a filtration medium.